Carburetor



2 n Will/[1111111111111 CARBURETOR E. P. DU PONT Filed Jan.

/A/ V E /V 701? Afro/Mik.

Sept. 4, 1923.

flea 795er@ /zu [du /csmr @www N Patented Sept ll, 1923;

rr srar PATENT oFFicE.

` nnnurrrnnn PAUL nu Penner non'rcneivrn, DELAWARE.

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Application inea January icrieez;` serial No. 528,271.

To all whom/it may concern:

, `Be it known that I, ELnUrHnnn yPAUL DU EONT, a citizen of the UnitedStates, residing at Montchaninf, county ofl New Castle,

and 'State of' Delaware,v have inventeda new and useful Improvement inCarburetors, of which the 'following is a full, clear, and exactdescription, reference being had to the accompanying drawings, `whichform a part of this specification. n Y

My invention relates'to an improvement in carburetors forinternal'combustionfen-` It is well known that internal combustionengines are difficult to startin cold weather on theordinary,runningmixturefor whichr their carburetors are normallyladjusted becauseof the difficulty of vaporizing gasoline at lowtemperatures, and'this difficulty is most seriousin automobile' engineswhich are frequently exposed to extreme cold for longk periods.

To obviate this difficulty, it is ycustomary to provide manuallyoperable means for shutting ofl or choking the air supply of thecarburetor, or to supply an increased quantityrof'gasoline tothemixtur'e` thuspr'oviding a richmixture which will be readily fired inthe cylinders at'low ltemperatures and result in an easy starting of theengine.

" The rich mixture provided for starting ar` cold engine is, however,highly injurious to the engine when 1t is warmed up, since 1t contains acertain amount of free gasoline,

which tends tol pass by the pistons andcon- .taminate thelubricatingoil` and which upon the firing of the mixture tends todeposit carbon, fbllurther, a warmed up motor will not operateefiiciently on a rich mixture and fuel is wasted. f Therefore, it isessential, in order to avoid inefliciencyand damage to the engine, that4the carburetor be permittedto 'deliver'a normal mixture assooneas theen- 'gine iswarmed up.

` It isrecognized that the drivers of automobiles'after having chokedtheirv carbuvretors for starting are prone to forget the choke andoperate their engines for long periods on a rich mixture with the'result that the engines are damaged as indicated.`

The object ofgmy inventionv is to provide means whereby thecarburetormay bemanually adjusted to supply a rich mixture for startingand at the same time means which will ,'actV automatically to return thecarbureto'r to normal when the engine has reached a mixture. Y f

" atemperature" at which it will operate etti-Y cientlyon the normalmixture which-the carburetor is adgusted to supply. Thus, whereas a richmixture may be supplied at anytime for starting a cold engine, thepossibility oi4 chamber "of the carburetor, which ,is kept suppliedwithgasolinevthrough pipe leadlng from a suitable source of supply. c isa 'vimixing tube into which leads a feed nozzle d in communication withthe float chamber through passage e. |The amount of gasoline yfedthrough-the nozzle CZ iscontrolled by a.

needle valve f. An air inlet g communicates `with the mixingtube and maybe led to a point adjacent the exhaustfmanifold of anr engine 'to enableasupply or" warm air.

The mixing tube c communicates with a passager' adapted to lead kthemixture to the engine, which is provided with a butterfiy type throttlevalve manipulation 'of' which serves to control the speedof the engine.

The carburetor is provided with an auxiliary air valve j, adapted to beopened by the suction of theengine, against the action of a spring le,as the speed increasesin order to supply additional air-tothe mixture atincreased engine speeds to compensate for 'the tendency' of the airrushingl bythe small aperture in nozzle e to draw anl excess of gasollnefrom the nozzle and supply too rich The Stem or the 'valve f is Snuabiypassed ythrough the bottom of the carburetor and is threaded at itsouter end and screwed throughy a nut Z, for adpistment, `which in turnis `pivotally vconnected toa lever m, which'is pivotally supportedfrom'they body ofthe carburetor rso that ywhen the lever is moved aboutits pivot,theneedlevalve'will bexmore or less entered or withdrawn fromthe feed nozzle d.' l' f f The lever m is adapted to be moveddownwardly, against the' action ofa spring n, to,`

open the valve f by means of a hand lever moving about the suitablynotched side of a quadrant p, positioned on the instrument board of anautomobile, through the medium of a rod g, one end of Which is pivotallyconnected to lever o While the other end is passed through lever m. Astop r is adjustably secured to rod g above the lever my, which whenIthe hand lever 0 is raised Will contact With lever m and push it down-Wardly. Vilhen the lever 0 is lowered, the stop ivill be Withdrawn fromlever m and spring n Will tend to raise the lever to contact with thestop toY impart a closing movement of the valve f. Y

A lever s provided adjacent one end with ratchet teeth z5 is pivotallysupported by the carburetor in such position as to permit the end oflever m to engage vvith the teeth t, whereby, when the lever isloivered, as above described, it Will be held in the position into whichit is moved. V

A thermostat u is positioned outside of a jacket o Which ,is adapted tocontain Water in circulation with the engine cooling' system, which actsto heat the` mixing tube and mixture passage orn the carburetor'. Thethermostat is so positioned es to act, when the engine is warmed up, onlever s to move it to free the ratchet teeth t from the end of lever m,permit the spring n to raise lever m and effect a closing movement ot'valve A hand lever w, adapted tor movement about a smooth side ofquadrant p, is connected to pivotally mounted on the carburetor by meansor a. rod The other arm of the bell crank lever is adapted, ivnen movedupwardly, to engage ivith detente z in a lever 41, pivot-ally mounted onthe carburetor. A spring` 5 is secured to the bell crank lever and tothe head of valve j, which, when the bell crank lever is raised, Will beput in tension and retard the opening oi valve j under the suction setup by the engine and thus retard the admission of auxiliary air.

The lever s is connected to the lever 4 by means of a link 6 so thatwhen lever s is moved by the thermostat u to free the end of lever mfrom teeth t, lever il: Will be moved to free the bell crank lever 1/from detents e and permit the bell crank lever and hand lever fw toassume normal position under the inlluence of spring 5 as it relievesitself of tension.

It Will noW be observed that in operation7 it the needle valve beadjusted to permit the proper amount of gasoline to pass through thenozzle, additional gasoline may be allowed to pass through the nozzle toobtain a rich mixture for starting by adjusting lever m downwardly bymeans of hand lever '1. The lever m will be maintained insuch positionagainst the action of spring n by the one arm of a bell crank lever y,

engagement of its end with teeth t on lever s andhand lever 0 may beimmediately returned to its normal position, thus p0sitioning stop r tolimit the upward movement of lever 'm when `it is released from teeth tWhen the engine is warmed up.

The auxiliary air valve is retarded from kopening until the venginewarms up, thus ifisuring a rich mixture for starting by means of aspring 5 which is normally out of tension, but which is tensioned byhand lever w, adjustment of which rotates Y`the bell crank lever y toincrease the length of the spring 5 and tension it. The bell crank leveris held in the position in Which it is adjusted by engagement With thedetente z in lever el. When the thermostat u acts 1o move lever s' clearof lever m, lever 4, through its connection With lever s, is moved clearof the bell crank and spring 5 relieves itself of tension, enablingvalve j to be actuated by the engine suction and returning lever w tonormal position.

Referring now to Figures 2, a thermostat u is positioned to operatedirectly on the stem of an air valve 7 g a jacketl 8, ycontaining Waterin circulation With the cooling system of the engine, being placed ov-erthe thermostat in order to cause it to actuate the valve when the motoris warmed up. Thus in the more simple types of carburetors, in which amere choking of the air supply Will su'flice to provide the necessaryrich mixture, the adaptation of my invention will be simplied.

Referring ncrv to Figure 3, a rod 9 is passed through the instrumentboard of the automobile andterminates in the button 10 by which the rodmay be slid back and forth. @n the other end is an eye 11 which may beconnected Vto any device on a carburetor as a choke valve, the purposeof which may be to facilitate starting When cold. A grooved portion 12of the rod 9 has placed against it a rounded piece 13 held incontact bya spring 14:. The piece 13 Will tend to drop into the notches or groovesin rod 9 so that the rod ivill snap into position and Will not be jarredout of position by vibra.- tion nor will it come out of position Withoutconsiderable force being applied to it in order to dis-engage the holdof the piece 13 in notches 12. The position of the rod 9 may be moved orchanged at any time irrespectivel of' Whether the piece 13 is in Contactwith it or not. The spring tends to push the rod outward, the tension ofthe spring le being such that the tension of the spring 15 is notsuilicient to push the rod unless the tension from the spring 14 isreleased. This is brought about by the action of the thermostat 16,influenced by heat from the circulation ,of a portion of the enginecooling Water in the space 17, which lifts the piece 13 from the grooves12, eauSng a llO the carburetor will function efiiciently at `efficie'ntengine temperature, and means oper able when the engine is ataneiiicient tem* perature to automatically effect a return of the fuelvalve to its predetermined adjust-l ment.

2. The combination with .a carburetor for internal combustion engines,comprising a fuel valve, means to adjust said Vvalve to a predeterminedposition to supply `an eiiicient amount of fuel, manually operable meanswhereby said valve may be opened to supply an excess amount of fuel forstarting the engine, and means operable automatically under theinfluence of the heat of the 'engine adapted to return said valve to itspredetermined adjustment after the engine, having been started, hasreached an eflicient temperature. c

3. The combination With a carburetor for internal combustion engines,comprising a fuel valve and an air valve, means to adjust said valves topredetermined relative positions to provide an eflicient mixture to theengine, manually operable means whereby the relative adjustment of saidvalves may be changed to provide an enriched mixture for starting theengine, and kmeans operable automatically under the` influence of theheat of the engine adapted to return said valves to their predeterminedrelative positions after the engine, having been started, has reached aneiiicient temperature.

4. The combination with a carburetor for internal combustion engines, ofan adjust-L able fuel valve, a pivoted lever supporting said valve,manually operable means for imparting movement to said lever to effectadjustment of said valve out of Vnormal for starting, means to fiX saidvalve in any desired adjustment for starting, and means actingautomatically to effect a return of-y said valve to any desi-red normaladjustment when the engine after starting vhas reached an eflicienttemperature.

5. The combination with a carburetor for internalcombustion engines,comprising a fuel valve and an auxiliary air valve, of manuallyVoperable means adapted to effect an'opening of said fuel valve greaterthan normal, normally inoperative means adapted toy be manually adjustedto retard the opening o f said auxiliaryy air valve, and means actingautomatically to permit said fuel valve to return to normal and renderinoperative said retarding'means when the engine is at an yeflicienttemperature.

6. The combination With a carburetor for internal combustion engines,comprisingy an adjustable'lfuel valve and an auxiliary air valve, ofmeans tending to maintain said fuel valve innormal adjustment, manuallyoperable means adapted to effect a change in the adjustment of said fuelvalve, means to maintain said valve in the position to which it ismanually adjusted, normally inoperative means adaptedto be manuallyadjusted to retard the opening of said air valve, means tending tomaintain said retarding means in adjusted position, and a thermostatadapted to be actuated at an efiicient enn gine temperature to releasesaid fuel valve and permit its return to normal and to ren-- der saidair valve retarding means inoperative. i

7. The combination with afcarburetor for f internal combustion engines,of manually adjustable means for effecting production by the carburetorof a mixture richer than normal for starting, means to maintain saidmanually adjustable means in adjusted position, means for warming thecarburetor, and a thermostat actuatable at an efficient temperature ofsaid Warmingmeans to release said maintaining means. and permitproduction by'the carburetor of a normal mixture.

y 8, The combination With a carburetor for internal combustion engines,of means to Warm the carburetor, means to increase the opening of thegasoline feed thereto, a spring tending to return said feed to normal, aratchet adapted to maintain said feed at an increased opening, and athermostat actuatable, When the carburetor is at an efficienttemperature, to release said ratchet and permit the feed to return tonormal.y

9.'The combination with a carburetor for l Vtemperature to release saidholding means.

In testimony of Which invention, I have hereunto set my hand, atVWilmington on this second day of December, 1921.

yELlilllTl-IERE PAUL nu PONT.

Witness: `Y v "SAMUnL'I-I. BAYNARD, Jr.

